Beneficiation of beryllium ores by froth flotation



Patented Jan. 19, 1954 UNITED STATES BENEFIcIArIm oF BERY PATENT OFFICE- 'No Drawing; Armenia-tune2339-512;

Slial' NO. 295128 F 1%.. t, {ff- 911 ,(Graiita'undef Iitler35; US. '06 e "(1952)",

,Sec."266) 'imiiitibh aes'rit''d herein 9 rousi mterial in, which them neral tmusfactured and used by qrior the Governme c absenteither having beenremovjed by the United States for goyernmental purposes without the paymentto meet any royalty thereon in accordance with the provisions of the Act ia ia dqe resul i i pier fi ber l, o ae n n l sired fonuse' in extraotive 'processes for beryl-- oi 's' i steer tat ringfniaterialsiwith pl qduction of a product'o'f sufficient beryllium content to be utilize'wby"extractive metallurgical processes.

hjet t i nv nt gn 157 1.07

for re'co'v ryj of bieryifr 1 11 a new. tb tmat J "ajcid' and water-soluble petroleum suln and at w ,o material may be employed directly upon any l; n seb aration meti looi s .ornot present in th e or ginalmaterial However, when the mineral f r p enti t e ry ii i s mat ria it is *adyantageoustq first isolate a berylfeld- .coneer trate from i h other. material by Ii ation, as, an uri grading, of flthe material is realized withfrespct to berylvprior to the final selecti e fbefyl flotation operation, 7 'l'h "prob is of this inventionwhen carried out on brylliferous pegmatitic orescontaining J coyite quartz and i olsp r, comprises grind n the j -berylliferou's material free the beryl and fihlimi e lq fro th othe fil s mi the groundmate'rial, re'rrim'iirig muscovite from the Qeslimed material, isolatingjeldspar ,and beryl together mm; the remaining materialv which, is main y uartz aRd Y1 neWe be y from the reldsriai. I ,M'usco'vita quartz, feldspar and beryl'are seriarately recovered as marketable prodii'c'ta} v Theberylliferous pegrnatitic material may e mashe w .zm nus 20 esh (Standard ,Tylei Screen) or finer Qa're should be taken to avoid the 'broductioniof; alarge amount of finesjf lf desired; thei nin'us20 -Inesh' material may be wet}! ground in a ball mill'or' other suitable apparatus witld'about equal amount ofjwaterto minus 35am h particle size; The degree of finenesfs tq lii h kieme je al mus be o nd is dep de t. moon the size at ,whichthebuk of the mineral particle areireeglone from thevother, and thus yaries ith thepartieul'arore treated. I A .The ground ore is deslimed by washing or by othermefthods knownto the artfor removing the r led li e, Q ..fine a cles-.. F rl xamp t eq e y v1 aeitetedvw water and the p deifilimesl decante v. .4

$. esl med ma riali ennt ea fl by fla -a:

' i n 9f y other po ven nt m thod f sde tive remov f mus covi'te Eor example, in re npvmg muscoyite flotation, V the deslimed sands may beagitated with, about an equaliweight of weekend ir me t pfiip d r l v ric acid, 9 2-9 og-. 5. p und. o a :Qhain .a1ky amine alth oll ctor; pr ferably coco amine"; ace-L tatQ ..tQl1 a1 rad an ..sm ll amount of br t s s h estlm thy ami'l a cohol, .in an amount not in excessho i 0.01, pounds; per tontof, fe d. Klin a itationhis. QQ nued Hforabout two pi hree minut istand t e pulp. is dilu edto about 25 per cent solids. Air is admitted and themuse covite resent s float d o f. inlt e ,fro malforme If. a high-grade muscovite product is desired, the

froth is retreated as many times as necessary t yield the graderequired It is to be understood, eve a he'p esent myention is nQtJde, pendent on any particular method of flotation of compounds and flotation with a collector of the V cationic type, such as an amine reagent, and a suitable frother.

For example, in floating feldspar and beryl from the muscovite flotation operation described above, the tailing or reject from this operation, without removal of any water, is conditioned for a period of 2 to 4 minutes by admixing 1 to 4 pounds of hydrofluoric acid to the ton of material treated,.0.1 to 0.3 pound of an amine collector, generally of the same type used in the muscovite flotation step, and 0.01 to 0.05 pound of frother, also of the same type used in the muscovite flotation step. Air is again introduced and a bulk beryl-feldspar is removed in the froth formed. Depending upon the mineral composition of the material being treated, the reject or tailing from this operation is usually a high grade quartz product, which may be cleaned if required by repeating the feldspar flotation step.

The bulk beryl-feldspar product is then conditioned with a given amount of either calcium or sodium hypochlorite or other material containing HClO or capable of releasing HClO upon acidification, hereafter called hypochlorite, depending upon the beryl content. The amount generally ranges from 0.5 to 2.0 pounds per ton of ore treated, and the time of conditioning is limited to not more than 5 minutes. The product is then washed for the removal of the hypochlorite and thickened to obtain a pulp of approximately 50 per cent solids. The thickened pulp is conditioned with a suflicient amount of sulfuric acid to maintain an acid pulp in the pH range of 2.0 to 3.0, a suitable amount of petroleum sulfonate of the water soluble or socalled green acid type, depending upon the amount of beryl present, and a small amount of frother of the mixed higher alcohol type. The quantities of these reagents usually employed in the flotation of the beryl from the feldspar are, in pounds per ton of material treated: sulfuric acid, 0.5 to 3.0 pounds; petroleum sulfonate, 0.5 to 2.5 pounds; and frother, 0.01 to 0.05 pound. The time of the conditioning period ranges between 2 and 3 minutes. After dilution with water to to per cent solids, the beryl is floated from the feldspar in the froth formed by these reagents. This froth is collected and may be retreated by the same procedure with additional small amounts of all the reagents, except for the hypochlorite, until the beryl content of the floated product has reached the desired grade. The cleaner tailings or residues from the retreatment maybe returned to any point in the operation for further treatment to recover the beryl present therein.

As aforementioned, the beryl flotation operation may be employed directly upon any berylliferous material in which muscovite is absent, and the invention, therefore, resides in this operation alone on such materials, and also in com- Al bination with the operations for separation of muscovite, quartz, and feldspar from berylliferous pegmatitic ores and similar berylliferous material.

The invention employs water solutions of hypochlorites, preferably either calcium or sodium hypochlorite, for the preparation and activation of the beryl mineral particles so that they can be selectively fllmed with the reagent combination of sulfuric acid and water soluble petroleum sulfonate. Either'soft or hard water may be used in this flotation procedure without adversely affecting the flotation of the beryl.

The flotation of the beryl mineral particles, while not limited to any particular theory of operation, is believed to be successful because of the following facts. Calcium hypochlorite has the chemical formula 2Ca\ 21120 0 C1 and when weakly acidified it liberates HClO, which is a powerful oxidizing agent hydrolyzing as follows:

Sodium hypochlorite reacts in a similar manner. This oxidizing agent apparently selectively reacts or modifies the surfaces of the beryl mineral particles to make them become selectively filmed when subjected to the conditions produced by the sulfuric acid, water soluble petroleum sulfonate, and a frother. The acid required for acidifying the hypochlorite is supplied, as the case might be, from the muscovite float or from the bulk beryl-feldspar float, or in the case of a muscovite-free material, it must be added if the bulk beryl-feldspar float is not employed.

The hypochlorite solution appears to perform a dual function when used in the conditioning of the bulk beryl-feldspar product in that it breaks down the heavy amine froth formed in this flotation step, thereby facilitating the washing of this product with a minimum mineral loss, as well as the above described apparent activation of the beryl.

The petroleum sulfonates are chemically complex mixtures derived from sulfuric acid treatment of various petroleum stocks. They may be classified into two broad types, those which are water soluble or green acids, and those which are hydrocarbon soluble or the mahogany acids. The water soluble type, or the so-called green acid, is the only type found suitable for the flotation of beryl. This compound has the following general chemical formula:

H-O-OH and may be regarded as a collector which selectively films the beryl mineral particles which have been pre-treated by the hypochlorite so that they will become attached to air bubbles and float.

The invention i further illustrated but is not limited by the following examples of practice:

EXAMPLE 1 Berylliferous pegmatitic material from the Peerless mine near Keystone, South Dakota, which contained 0.5 per cent beryl in a gangue composed essentially of feldspar, quartz, and muscovite, with lesser amounts of tourmaline, apatite, and purpurite, was treated in accordance with the process of the invention. The

Circuit 1 tional dataiand the'resmtsmfth'is' test-are'givem in: the following tables: Ob'rzftionzihdatii Circuit uecevi te iBeryl-feldspar Beryl 0 d 0 d 1 Conditioner Cleaner 5 Rougher 3 R ougher Rougher Sulfuric-acid1bs=/ton.-.; I: 4.

new. A,

Results 0 flotation Prddiicf I Percent beryl beryl y1 Beryl cleaner N0; 2. Beryl cleaner No. 1...

Berymimus =pegmatitic -E materialfrom v thesarmi'mineelfiExample lebut whicha contained 1.9 pemfc'em; ery1- wassimilarly treated -in-accordaneee withwthe:e-process of this zeinventiom" The Opeiatiohdi data Results of flotation A fourth sample of berylliferous material from the Peerless mine, containing similar gangue minerals as the three foregoing samples but which contained 10.7 per cent beryl, was treated by the process of the invention. The operational data and results of the treatment are as follows:

Operational data berylllferous'pegmatitic materials. Although the procedure has been described in connection with concentration of beryl from pegmatitic gangue materials and is especially useful with this material, it is applicable to other beryl-bearing ores as well.

It willbeappreciated from a reading of the foregoing specification that the invention herein described is susceptible of various changes and modifications without departing from the spirit and scope thereof.

What is claimedis: r v

1. A process for the flotation of beryl from berylliferous material comprising treating a pulp of the berylliferous material, with a hypochlorite solution to activate the beryl particles for flotation, and then froth floating the beryl particle from the residual gangue in thepresence of a water-soluble sulfonate.

2. A process for the flotation of beryl from berylliferous material comprising treating a pulp Circuit Muscovite Beryl-feldspar Beryl Reagents (tlpndiioner 33%;; Rougher i353. Rougher Rougher Cleaner Sulruric acid lbs/ton Coco amine acetate (technical grade) Methyl amyl alcohol Calcium hypochlorite. Petroleum sulionatc. Hydrofluoric acid Results of flotation Analysis Percent Wei ht Product percent of total percent beryl beryl 6. 3 0. 1 w 0. 1 l0. 8 80. 80. 3 4. 5 3. 0 1. 2 47. 6 2. 9 l2. 7 19. 0 4. 2 5. 7 l1. 8 trace nil Composite heads.... 100.0 10.7 100.0

in a berylliferous pegmatitic material containing 10.7 per cent beryl was treated, a product was obtained which-analyzed 80.0 percent beryl and contained 80.3 per cent of the beryl of the original material. In Examples 2 and 3, a recovery of 87.2 and 84.6 per cent of the original beryl was realized and the products analyzed 65.0 and 78.0 per cent beryl, respectively. All of these products are suitable for use in direct extractive processes for recovery of beryllium.

It is apparent from the foregoing descriptions and examples that a desirable treatment ha been provided whereby beryl can be concentrated from of the berylliferous material with a, hypochlorite solution to activate the beryl particles for flotation, acidifying the solution, and then floating the beryl particles from the residual gangue with a water-soluble petroleum sulfonate and a frothing agent.

3. The process of claim 2 in which a calcium hypochlorite solution is employed to activate the beryl particles.

4. The process of claim 2 in which a odium hypochlorite solution is employed to activate the beryl particles.

5. A process for the flotation of beryl from berylliferous material comprising treating a pulp of the berylliferous material with a hypochlorite solution to activate the beryl particles for flotation, adjusting the pH of the resulting pulp to about pH 2.0 to 3.0, agitating the pulp with a Water-soluble petroleum sulfonate and a frothing agent, and floating the beryl particles from the residual gangue.

6. A process for the flotation of beryl from berylliferous material comprising treating a pulp of the berylliferous material with about 0.5 to 2.0 pounds of a hypochlorite per ton of material, washing the treated pulp, conditioning the treated pulp with about 0.5 to 3.0 pounds of suliuric acid, about 0.5 to 2.5 pounds of water soluble petroleum sulfonate, and about 0.01 to 0.05 pound of methyl amyl alcohol per ton of material, and selectively floating the beryl from the residual gangue.

7. A process for concentrating beryl from berylliferous material containing feldspar and other gangue minerals comprising subjecting the berylliferous material to a cationic flotation operation to isolate a feldspar-beryl concentrate, activating the, beryl-particles of the feldspar-beryl concentrate by treatment with a hypochlorite solution, and then froth floating the beryl from the feldspar in the presence of a water soluble sulfonate.

8. A process for concentrating beryl from berylliferous pegmatitic ores containing muscovite, feldspar, beryl, quartz,nand other gangue materials, comprising grinding and desliming the ore, agitating the deslimed material with sulfuric acid. an amine collecting agent and a frothing agent, selectively floating oil the muscovite, conditioning the remaining material with hydrofluoric acid, an amine collecting agent and a frothing agent, selectively floating oil a beryl-feldspar concentrate activating the beryl particles of the beryl-feldspar concentrate by treatment'with a hypochlorite solution, conditioning the treated material with sulfuric acid, a water soluble sulfonate and. a frothing agent, and selectively fioating the beryl particles from the feldspar.

SIDNEY M. RUNKE.

References Cited in the file of this patent UNITED STATES PATENTS OTHER REFERENCES T. P. Aimme, 1074 in Mining Technology. vol. 3, May 1939.

Bureau of Mines, Report of Investigation 4040, March 1947. 

1. A PROCESS FOR THE FLOTATION OF BERYL FROM BERYLLIFEROUS MATERIAL COMPRISING TREATING A PULP OF THE BERYLLIFEROUS MATERIAL WITH A HYPOCHLORITE SOLUTION TO ACTIVATE THE BERYL PARTICLES FOR FLOTATION, AND THEN FROTH FLOATING THE BERYL PARTICLE FORM THE RESIDUAL GANGUE IN THE PRESENCE OF A WATER-SOLUBLE SULFONATE. 